The Parameter Space Occupied by Galaxies : The optical window
نویسندگان
چکیده
We discuss the optical parameter space (luminosity and surface brightness) over which galaxies are known to exist and report on the results from three recent datasets: the Two-degree Field Galaxy Red-shift Survey, the Hubble Deep Field north, and the Local Group. These data are combined to provide a unique and comprehensive insight into the luminosity distribution of galaxies over the range −24 < M B < −8 mags, and the surface brightness distribution over the range 18 < µ e < 28 mags/2 ′′. The main conclusions are: (1) luminous low surface brightness galaxies are rare; (2) there exists a universal luminosity-surface brightness relation; (3) the most numerous galaxies are low luminosity low surface brightness dwarfs.
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